Closure for tank apertures



Filed Fleb. 21, 1933 IN V EN TOR. 6mm 70. 039W.

ATTORNEY Patented Oct. 25, 1938 UNITED STATES PATENT OFFICE 2 Claims.

This invention relates to a closure for apertures such as manhole openings in tanks and like metal containers.

The object of the present invention is to generally improve and simplify the construction and operation of removable covers; to provide a readily operated fastening means whereby a manhole cover may be quickly applied or released; and particularly to provide a fastening means which is carried by the cover and removable therewith so as to leave a free and unobstructed opening through which entrance orexit may be readily made.

The cover and fastening means are shown by way of illustration in the accompanying drawing in which- Fig. 1 is a plan view of the manhole cover and the fastening means;

Fig. 2 is'a side elevation of. the same;

Fig. 3 is an enlarged cross-section taken on line III-IH showing the cover in closed position and the bolts secured;

Fig. 4 is a similar section showing the bolts in released'position and the cover ready for removal; and

Fig. 5 is a perspective view of one of the bolt Washers.

Containers such as tanks, and even boilers, are often provided with manhole openings and covers which are secured by bolts and the like. Either pivoted bolts or stud bolts are usually employed, and they extend through the cover and are secured by nuts threaded to the bolts and engaging the face of the cover. When the nuts and cover are removed, the bolts usually surround the manhole opening, and as such, make it diflicult for an operator to enter, as his clothing will invariably get caught on one or another of the bolts. The present invention relates to a removable manhole cover which leaves a free unobstructed opening for an operator to crawl through.

Referring to the drawing in detail, and particularly Figs. 2, 3 and 4, B indicates a portion of a tank, and 2 an opening formed therein. Secured around the opening is a rim H on the outer face of which is formed a hook-shaped annular flange IS. The cover proper is indicated at It and is provided with an annular flange I! on which are formed pairs of spaced lugs I8. A bolt 19 is disposed between each pair of lugs. Each bolt is slotted longitudinally as shown at 20, and is secured against removal by pins 2|. The bolts are free to pivot about the pins 2|, and they are also longitudinally removable with relation thereto, as will hereinafter appear.

The upper ends of the lugs are provided with flat faces 22 and angular faces 23. A washer such'as shown at 24 (see Figs. 3, 4 and 5) is placed over each bolt, and on top of the lugs and cooperating therewith are wing nuts 25.-

Flg. 3 shows the cover in closed position. In this position the lower hook-shaped ends 21 of. the bolts engage the rim or flange l5, and by tightening the wing nuts 25, the cover will be pulled against the rim l4 and there secured. If it is desired to release the cover, it is only necessary to loosen the wing nuts and to swing the bolts about their pivots to assume the position shown in Fig. 4. By again tightening the wing nuts, the bolts will be held against pivotal movement about the pins 2|, and will furthermore be held in a position which permits the cover to be readily removed or applied as the case may be, asthe hook-shaped ends 21 are held outwardly free of the rim or flange l5.

The washer 24 (see Fig. 5) is an elongated washer with a hole 24a at one end to permit it to be slipped over the bolt. The washer is also bent to fit the angular faces 22 and 23 of the lugs, and is furthermore provided with a lug 24b which extends into the space formed between each pair of lugs so as to secure the washer against rotation and the nuts being tightened.

When the cover is in place and. secured by tightening of thebolts I9, the washers 24 will assume the position shown in Fig. 3that is, the lugs 2417 will engage the space between the angular faces 23 of the lugs l8. When the bolts are released, as shown in Fig. 4, the washers are r0- tated a half-revolution so that the lugs 24b will engage or extend downwardly between the faces 22 of the lugs Hi. In either position, the washers are held against rotation so that the nuts may be tightened or released without displacing the washers.

When the cover is released, as shown in Fig. 4, it may be lifted off or completely removed, and an entirely free or, unobstructed opening is effected for the operator to enter or make an exit from without danger of any of his clothing being caught by any bolts, lugs or other protuberances. If desired, the cover may be hinged as shown at 26 (see Figs. 1 and 2) and as such, may be swung to one side when the manhole is to be opened.

While these and other features of the present invention have been more or less specifically described and illustrated, I wish it understood that various changes may be resorted to within the scope oi. the appended claims, and that the materials and finish oi the several parts employed may claim and desire to secure by Letters Patent is- 1. The combination with a container having an opening formed therein or a rim member secured to the container and surrounding the opening, a cover seated on the rim and forming a closure for the opening, a plurality of bolts pivotally mounted on the cover and having hook-shaped lower ends movable into and out of engagement with the rim, said bolts being longitudinally movable with relation. to their pivots, a nut on each bolt to draw the cover tight, and means ior securing the bolts against pivotal movement when their lower hook-shaped ends have been swung outwardly away from the rim.

snags 2. The combination with a container having an opening formed therein oi a rim member se-, cured to the container and surrounding the opening, a cover seated on the rim and iorming'h closure for the opening, pairs of spaced lugs on the cover. a bolt pivoted between each pair oi lugs, said bolts being longitudinally slotted to permit longitudinal movement or the bolts between the lugs, a hook-shaped lug on each bolt engageable with the rim, a face on each pair of lugs parallel with the cover, a second face on each pair of lugs disposedson an angle with relation to the face otthe cover, an elongated washer for each'boit, said washer being bent to engage both the parallel and angular faces of the lugs, a nut on each bolt and engageable with the washers, and means for securing the washers against rotation when the nuts are rotated.

EDWARD M. ODONNELL. 20 

